Exhibit 12

Potash Corporation of Saskatchewan Inc.

Ratio of Earnings to Fixed Charges

(in millions of US dollars, except ratio amounts)

(unaudited)



|                                                        |  |                        |       |   |      |   |       |      |  |   |       |   |  |      |       |   |  |   |       |  
|------------------------------------------------------- |  | ---------------------- | ----- | - | ---- | - | ----- | ---- |  | - | ----- | - |  | ---- | ----- | - |  | - | ----- | -
|                                                        |  | Year ended December 31 |      
|                                                        |  | 2015                   |       |   | 2014 |   |       | 2013 |  |   | 2012  |   |  | 2011 |      
|Net income                                              |  | $                      | 1,270 |   |      | $ | 1,536 |      |  | $ | 1,785 |   |  | $    | 2,079 |   |  | $ | 3,081 |  
|Income taxes                                            |  |                        | 451   |   |      |   | 628   |      |  |   | 687   |   |  |      | 826   |   |  |   | 1,066 |  
|Share of earnings of equity investees                   |  |                        | (121  | ) |      |   | (102  | )    |  |   | (195  | ) |  |      | (278  | ) |  |   | (261  | )
|Fixed charges                                           |  |                        | 250   |   |      |   | 253   |      |  |   | 259   |   |  |      | 272   |   |  |   | 300   |  
|Amortization of capitalized interest                    |  |                        | 29    |   |      |   | 27    |      |  |   | 23    |   |  |      | 18    |   |  |   | 14    |  
|Distributed income of equity investees                  |  |                        | 86    |   |      |   | 172   |      |  |   | 180   |   |  |      | 211   |   |  |   | 128   |  
|Interest capitalized                                    |  |                        | (40   | ) |      |   | (41   | )    |  |   | (79   | ) |  |      | (102  | ) |  |   | (84   | )
|Total Earnings Available for Fixed Charges              |  | $                      | 1,925 |   |      | $ | 2,473 |      |  | $ | 2,660 |   |  | $    | 3,026 |   |  | $ | 4,244 |  
|                                                        |  |                        |       |   |     
|Fixed Charges                                           |  |                        |       |   |      |   |       |      |  |   |       |   |  |      |       |   |  |   |       |  
|                                                        |  |                        |       |   |     
|Interest expensed and capitalized                       |  | $                      | 222   |   |      | $ | 225   |      |  | $ | 231   |   |  | $    | 244   |   |  | $ | 273   |  
|Amortization of debt issue costs                        |  |                        | 5     |   |      |   | 5     |      |  |   | 5     |   |  |      | 5     |   |  |   | 5     |  
|Estimated portion of rent expense representing interest |  |                        | 23    |   |      |   | 23    |      |  |   | 23    |   |  |      | 23    |   |  |   | 22    |  
|Total Fixed Charges                                     |  | $                      | 250   |   |      | $ | 253   |      |  | $ | 259   |   |  | $    | 272   |   |  | $ | 300   |  
|Ratio of Earnings to Fixed Charges                      |  |                        | 7.70  |   |      |   | 9.77  |      |  |   | 10.27 |   |  |      | 11.13 |   |  |   | 14.15 |